I’d experienced random shutdowns when the battery capacity was under ~70% and during power-intensive operations (CPU, display backlight). The default voltage_min_design value was 3.3V. I lowered it to 2.9V, and everything works fine now. Unfortunately, I also started charging calibration, so I can’t be sure what fixed the issue.
My 18650 battery Cutoff Voltage is 2.5V. Min voltage of 3.3V seems too high for me. Does some default power management tool in Debian use voltage_min_design to cut the power when voltage drops below voltage_min_design? It certainly looked like this. But is it correct?
I’ve been wondering about this, too. I tried setting the POWER_SUPPLY_VOLTAGE_MIN_DESIGN=2900000 attribute in /etc/udev/rules.d/99-uconsole-charging.rules but have not observed any change in behavior.
I regret to inform you that you have a dud battery. When the battery isn’t able to supply sufficient voltage, the uConsole shuts down. Telling the battery module to supply more current won’t help.
Source: I had a dud pair of batteries and then I replaced them. Went from about 2.5 hours of battery life with random shutdowns to 7.5 hours. I’ve had good luck with a pair of Samsung 35Es, but it seems like there’s a bit of a battery lottery when ordering 18650s online.